Electric switch



Feb. 5 1924.l 1,482,958

E'. H. W. ULLRICH ELECTRIC SWITCH INVENTOR Em/L HJM ULLR/CH ATTORNEYS Feb. 5 1924..

E. H. W. ULLRCH ELECTRc SWITCH Filed May l2. 1921 2 Sheets-Sheet 2 I l l I l l\ w MQNW INVENT'DR EMIL H. W. ULLR/cu BY JW Wm Parma-d Fel.l -sr 1924i.I

UNITED STATES PATENT OFFICE. i

EMIL H. w. ULLRICH, C F NEW vomir,v N. Y., `AssIeNor. 'ro TBE BRYANT I-:Llazcnucl con- PANY, or BaIDoEPoIvr, CONNECTICUT, A ConPoaA'rIoN or CONNECTICUT.

ELECTRIC SWITCH.

Application led Hay 12, 1921.

To all whom 'it may con-cern.:

Be it known that I, EMU. H. WV. ULLmcH, a citizen of the United States of America, residing in New York city, borough of Manhattanfin the county of New York and State of New York, have invented certain new and useful Improvements in Electric Switches of which the `following is a specification.

My invention relates to electric switches, and particularly to the type of switch commonly referred to as an entrance switch, which control the connection between the wire mains and a distributing panel, although the switch may be used in any installation to which it is suited. .Among the objects of my invention I may particularly mention, first, the provision of a switch having a housing of such construction that it cannot be opened while the switch is closed; second, an insulating shield so arranged that when the switch is opened the shield obstructs Contact with the terminals connected to the mains; third, a simple and effective device for securingA a quick break of the switch; fourth, a switch havingl its contacts encased at all times in insulation, through which narrow guide slots are formed to permit the ent-ry .of the Switch blades through restricted passageways, thus, not only insuring a proper engagement lbetween the switch blades and the switch contacts, but also minimizing the danger of are format-ion on the opening of the switch; fifth, a simple andrugged construction of the switch-operating parts. so that they are not only readily manufactured and-assembled` but also eilicieut in service; sixth, a compact fuse arrangement for the switch, the fuses being so positioned that they may be readily renewed, but only in the open position of the switch, and without danger to the operator; seventh, various detailsof construction hereinafter described or indicated in the accompanying Fig. 3 is asimilar view showing the casing closed, but the switch open; and

Fig. 4 is a section on the line 4 4, Fig. 3. The present switch is provided with a box- Serial No. 468 ,909.

like metal housingor casing 5 having knockouts 6 for the admission of conduit or armored cable, through which the incoming mains 7 and outgoing leads 8 are led to or from the switch. The box may be mounted by means of bolts or screws 9 on any suitable support, for instance on the bottom of the casing (not shown) of a distributing panel. Its cover 10 is hinged at 11 to one of the box sides, and is provided with a lug 12 registering with a lug 13 on the body, both apertu red at 14. to receive the shackle of a padlock 15 (Fig. 2), by which the box may be locked closed.

Tithin the box and resting a ainst the bottom. thereof is a connection b ook 16 of msulatmgmaterial, such as porcelain, which is secured in position by means of suitable screws 17 taking into tapped holes in the bottom of the box. Spaeed apart on .the block 1G are spring clip switch contacts 18, 19, two pairs for a double-pole switch, being shown in the present drawing. These contacts have associated therewith bindingscrew extensions 20 tapped to receive the screws 21 by which the mains and branch leads are mechanically secured and electrically connected. To render the const-ruction more compact, and to interpose insulating barriers between the conductors, the wire terminals and switch contacts are let into wells 22 in the upper face of the connection block. so that only the free ends of the contact clips project above the upper face of the block. and only to a slight extent.

Overlying the connection block and housing-iu the conductors thereon is an insulating cover block 23 substantially co-extensive with the connection block 16, and secured thereto by screws 24, which take into tapped rivets 25, or their equivalents. On its inner `face the cover block 23 is suitably recessed at 26 to accommodate the rojecting ends of the Contact clips 18, 19,-wiiile slots 27 piercingthe block register with the clips andform guides for the co-operating switch blades 28 and 29. The outer face of the cover block is also recessed at 30 to accommodate the fuses 31 and 32 when the switch is in closed position.

The switch blades 28 and 29, and fuses 31 and 32 are carried by a switch block 33 of insulation, which is also of substantially the same rectangular' cont-our as the connection block and cover block. As here shown the blades 28 and 29 are formed from strap metal. Their offset base flanges are accommodated in a recess on the inner face of the switch block 33 pierced to receive the Shanks of securing screw-bolts 34. Underlying the nuts on the ends of the screw-bolts and contacting with the bases of the switch blades arev spring clips 35 and 36, which receive the terminal ferrules 37 of cartridge fuses, and not only mechanically support the same in position, but electrically connect each fuse interposed between a pair of co-operating switch blades 28 and 29.

To open the switch a handle 38 is provided, having a stem 39, which passes in through the cover 10 of the boX and is connected to the outer face of the switch block 33. In order to insure a quick break between the switch blades and contacts, I mount centrally on the inner face of the switch block 33 a double-arm spring` plunger Ll() which co-operates with a spring fork l1 mounted on the connection block 16 and projecting through the cover block 23. The spring plunger 110 is preferably formed from spring strap metal offset at 42 and 4-3 to receive the beads 44 formed at the ends oi' the. arms of the spring fork Ll-1.. T he oii'sets 42 and 43 are so located that when the switch is in the on position (Fig. 2) the beads 44 of the yoke engage in the oii'set 42, while when the switch is open they engage in the offset d'3. The switch block is thus mechanically held in both opened and closed positions by the plunger O and co-operating fork 41, while the eii'ort required to free the plunger from the grip of the beads-on the spring fork, insures a sudden outward pull of the switch block 33, and thus a quick break of the switch. lThe central location ot the plunger and fork amply spaces these parts from the conductors of the switch. and from the ferrules ot the cartridge fuse, so that there is no danger of short the switch block 33, as a whole` is guided in the casing cover 10 by its relatively snug tit within the sides thereof, so that an accurate rectilinear motion o' the block is insured on the switch opening and closing movements.

ln order to lock the switch in out of service position, so that it cannot be closed, a hole 45 may be formed in the. shank 39 ot the stem oit the switch handle 38 to receive theshackle of a padlock above the cover of the box.

From the foregoing description it is obvious that while the casing 5-10 may be closed and locked by the padlock 15, the switch is still readily operable within the casing without opening the latter. This is an important emergency provision, since immediate opening of the switch is highly desirable, should it be necessary to break the circuit by reason of any accident or defect occurring in the circuit controlled thereby. At the same time, the arrangement prevents unauthorized tampering with the switch. The hole 45 in the stem of the switch handle permits the switch to be locked out of service,7 when for any reason this is desired.

The re-fusing of the switch is rendered perfectly sate, since not only are the fuses located between the adjacent faces of the cover block 23 and the switch block 33, but it is furthermore impossible to obtain access to the interior of the switch easing until the switch has been opened. This is obvious since the handle 38 is so designed as to closely approach the casingcover 10 when the switch is closed. switch blades carried by the switch block are in engagement with the cooperating members on the connection block, and with the cover block 23 in circuit closing position, and this engagement also prevents the opening of the box while the switch is closed. Thev switch block 33 and its associated elements, forms in effect a locking block which prevents the opening of the box until the switch block 33 has been moved outward into the cover, to open-switch position. lVhen the casing cover 10 is swung open, the block 33 is carried thereby and the fuses 3l and 32 are at a point remote from the `live contacts on the switch base. Moreover, the switch contacts are complet-ely housed-in except for the narrow slots 27 in the cover vblock 23, which is secured to the connection block 16.

Obviousy, the spring yoke 4:1 is electrically dead, and its projection beyond the face of the cover plate involves no danger.

The construction as a whole is simple and rugged, the porcelain parts are readily molded, the metal parts are readily shaped from sheet metal, and the box is simply designed.

It may also be specially pointed out that. the construction is such that all the features of safety are maintained whether the power and load mains are connected to the terminals at one end or the other ot the connection block. In other words, the power and load wires can be interchangeably connected to the terminals on the block without losing the safety features ot construction, since when the switch is opened for re-fusing` all the switch blades are dead, regardless of the manner in which the wires are connected to the wire terminals.

Various modifications in details of structure and contour will readily occur to those dealing with the problem without` however, departing in any way from what I claim as my invention.

l claim- 1. A switch of the character described,

Moreover, the plunger 14 and' comprising a connection block, switch contacts and associated terminal connections thereon, a cover block of insulating material mounted on and secured to said connection block and covering the electrical conductors thereon, said block beingapertued in register witli'tthe `switch 'contact's,''together;with an iride endeit switch* block*l of insulating trically:connect` a fuse Vbetween said yIswitch blades; a `boxv vencasin,r f. said parts, `and `a switch operating handle passing through the said box and connected to said switch block fo shifting thelatter rectilinearly to openv-orclosethelsw'itcln said switch box having side walls affording a guide for the switch block during its switch opening land closing movements.

Q. A switch Vof the character described, comprising a connection block, switch contacts and associated terminal connections thereon, a cover block of insulating material mounted on and secured to said connection block and covering the electricalconductors thereon, said block being apertured in register with the switch contacts, together with an independent switch block of insulating material, switch blades thereon, associated fuse terminals adapted to receive and electrically connect a fuse between said switch blades, a box encasing said parts, and a switch operating handle passing through the top of said box and connected to said switch block for shifting the latter rectilinearly to open or close the switch, together with detaining means associated with the connection block and cooperating with means associated with the switch block, means'for effecting a quick break between the switch contacts and the switch blades on the opening of the switch.

3. A switch of the character described, comprising a connection block., yswitch contacts and associated terminal connections thereon, a cover block of insulating material mounted on said connection block and covering the electrical conductors thereon, said block being apertured in register with the switch contacts, together with an independent switch block of insulating material, switch blades thereon, associated fuse terminals adapted to receive and electrically connect a fuse between said switch blades, a box encasing said parts, and a switch operating handle passing through said box and connected to` said switch block for shifting said switch block rectilinearly to open or close the switch, together with spring detent means insulated from the conductors and comprising cooperating elements on the connection block and switch block for etl'ecting a quick break between the switch contacts .connect a and the switch blades on the opening of the switch.

4. A switch of the character described, comprising a connection block, switch contacts yand associated terminal connections thereon, a cover block of insulating material lmounted on said connection block and covere ing the electrical conductors thereon, said materia switehbladels thereon, associated 1' fuseterrrials adapted to'receive and elecblockrbeing apertuaed in re ister with the switch contacts,togetherwit an independent ,switch block of insulating ,material,

switch bladeslthereon, associated fuse terminals adafted to vreceive and electrically use between saidk switch blades, a box encasing said parts, and a switch operating handle passin through said box and connected to said switch block for shifting said switch block rectilinearly to open or close the switch, together with a plunger carried by the switch block, a co-operating spring fork associated with the connection block and cover, and engaging means between said plunger and fork to yieldingly detain the switch block against its movement to open switch position.

5. A11 electric switch comprising a connection block, terminals and switch contacts carried thereby, an insulating cover plate overlying said terminals and switch contacts and apertured in register with the latter to permit'the insertion of switch blades therethrough into engagement with the contacts onthe conection block, in combination with an insulating switch block, switch blades mounted thereon in register with the switch contacts, associated fuse terminals adapted to support a fuse between the switch and cover blocks, said cover block being recessed to accommodate a fuse mounted in said fuse terminals, in the closed position of the switch.

6. An electric switch comprising a connection block, terminals and switch contacts carried thereby, an insulating cover plate overlying said terminals and switch contacts and apertured in register with the latter to permit the insertion of switch blades therethrough into engagement with the contacts on the connection block, in combination with an insulating switch block, switch blades mounted thereon for engagement with the switch contacts on the connection block, fuse terminals electrically associated with the switch blades, said switch block resting upon the insulating cover plate in closed switch position, together with fuses mounted in said fuse terminals and housed between the switch block and insulating cover plate in closed position of the switch.

In testimony whereof I have signed my name to this specification.

EMIL H. 3V. ULLRICH.

Certificate of Corre-ration.

llt ie hereby certified that in Lettere Patent No. 1,482,958, granted February 5, 1926.-? 'apen the application of Emil H. W. Ullrich, of New York, N, Y., for an improvement in l Electric Swtches, an error appears in the printed specification requrngeerrection as follows: Page 3, line 14, claim 1, after the article the yinsert the Words 0p 0f; 2mdthet the. Said Letters Patent should be read. with ftl'rl'e correctien therein that the same 'may conform to the record of the case 'in the Patent @Hice Signel mtl sealed tne th day of March, A. D., 1924.

[SEAL] KARL FENNING, I Acting (/lommz'ssz'onm* of Przen 

